1. Field of the Invention
The present invention relates to a chip package structure, and more particularly to a chip package structure with a shielding cover.
2. Description of Related Art
An integrated circuit (IC) chip is often electrically connected to a motherboard through a circuit board, so as to allow electronic signals to be transmitted between the IC chip and the motherboard. Nevertheless, the higher a clock frequency of the IC chip is, the easier the electronic signals suffer from electromagnetic interference (EMI). In order to prevent stability of the IC chip from being affected by EMI, a metal cover is frequently disposed on top of the circuit board for avoiding electromagnetic wave leakage or precluding the circuit board from being interfered by an external electromagnetic wave.
At present, the metal cover can be disposed on the circuit board by applying a pin through hole (PTH) technique or a surface mount technology (SMT). In the conventional SMT, conductive paste or solder paste are printed (inkjet printed or screen printed) on the back of the circuit board, and thereby ends of leads of the metal cover are directly bonded to pads on the circuit board by means of the conductive paste and or the solder paste. Nonetheless, in a process of baking and solidifying the conductive paste or in a reflow process for transforming the solder paste to be in a liquid form, heat convection generated thereby results in shift and deflection of the metal cover. As a result, the metal cover disposed on the circuit board cannot be accurately positioned on the pads of the circuit board, and yield of assembling the metal cover is negatively affected.